package com.lenovo.flutter_with_bmap.util;

public class GpsHandle {
    private static final double pi = Math.PI;
    private static final double a = 6378245.0;
    private static final double ee = 0.00669342162296594323;
    private static final double x_pi = 3.14159265358979324 * 3000.0 / 180.0;
    public static double[] wgs2bd(double lat, double lon) {
        double[] wgs2gcjR = wgs2gcj(lat, lon);
        double[] gcj2bdR = gcj2bd(wgs2gcjR[0], wgs2gcjR[1]);
        return gcj2bdR;
    }

    static double[] gcj2bd(double lat, double lon) {
        double x = lon, y = lat;
        double z = Math.sqrt(x * x + y * y) + 0.00002 * Math.sin(y * x_pi);
        double theta = Math.atan2(y, x) + 0.000003 * Math.cos(x * x_pi);
        double bdLon = z * Math.cos(theta) + 0.0065;
        double bdLat = z * Math.sin(theta) + 0.006;
        double[] result = {bdLat,bdLon};
        return result;
    }

    public static double[] bd2gcj(double lat, double lon) {
        double x = lon - 0.0065, y = lat - 0.006;
        double z = Math.sqrt(x * x + y * y) - 0.00002 * Math.sin(y * x_pi);
        double theta = Math.atan2(y, x) - 0.000003 * Math.cos(x * x_pi);
        double ggLon = z * Math.cos(theta);
        double ggLat = z * Math.sin(theta);
        double[] result = {ggLat,ggLon};
        return result;
    }

    public static double[] wgs2gcj(double lat, double lon) {
        double dLat = transformLat(lon - 105.0, lat - 35.0);
        double dLon = transformLon(lon - 105.0, lat - 35.0);
        double radLat = lat / 180.0 * pi;
        double magic = Math.sin(radLat);
        magic = 1 - ee * magic * magic;
        double sqrtMagic = Math.sqrt(magic);
        dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * pi);
        dLon = (dLon * 180.0) / (a / sqrtMagic * Math.cos(radLat) * pi);
        double mgLat = lat + dLat;
        double mgLon = lon + dLon;
        double[] result = {mgLat,mgLon};
        return result;
    }

    public static double[] bd2wgs(double bdLat, double bdLon) {
        double[] gcj02 = bd2gcj(bdLat, bdLon);
        double[] map84 = gcj2wgs(gcj02[0], gcj02[1]);
        return map84;
    }

    public static double[] gcj2wgs(double lat, double lon) {
        double[] gps = wgs2gcj(lat, lon);
        double lontitude = lon * 2 - gps[1];
        double latitude = lat * 2 - gps[0];
        return new double[]{latitude, lontitude};
    }

    static double transformLat(double lat, double lon) {
        double ret = -100.0 +
                2.0 * lat +
                3.0 * lon +
                0.2 * lon * lon +
                0.1 * lat * lon +
                0.2 * Math.sqrt(Math.abs(lat));
        ret +=
                (20.0 * Math.sin(6.0 * lat * pi) + 20.0 * Math.sin(2.0 * lat * pi)) * 2.0 / 3.0;
        ret += (20.0 * Math.sin(lon * pi) + 40.0 * Math.sin(lon / 3.0 * pi)) * 2.0 / 3.0;
        ret +=
                (160.0 * Math.sin(lon / 12.0 * pi) + 320 * Math.sin(lon * pi / 30.0)) * 2.0 / 3.0;
        return ret;
    }

    static double transformLon(double lat, double lon) {
        double ret = 300.0 +
                lat +
                2.0 * lon +
                0.1 * lat * lat +
                0.1 * lat * lon +
                0.1 * Math.sqrt(Math.abs(lat));
        ret +=
                (20.0 * Math.sin(6.0 * lat * pi) + 20.0 * Math.sin(2.0 * lat * pi)) * 2.0 / 3.0;
        ret += (20.0 * Math.sin(lat * pi) + 40.0 * Math.sin(lat / 3.0 * pi)) * 2.0 / 3.0;
        ret += (150.0 * Math.sin(lat / 12.0 * pi) + 300.0 * Math.sin(lat / 30.0 * pi)) *
                2.0 /
                3.0;
        return ret;
    }
}
